Field
The present disclosure relates generally carbon-based electrodes for energy storage devices, and more specifically to carbon-based electrodes exhibiting high-voltage stability and their methods of production.
Technical Background
Energy storage devices such as ultracapacitors may be used in a variety of applications such as where a discrete power pulse is required. Example applications range from cell phones to hybrid vehicles. Ultracapacitors such as electrochemical double layer capacitors (EDLCs) have emerged as an alternative or compliment to batteries in applications that require high power, long shelf life, and/or long cycle life. Ultracapacitors typically comprise a porous separator and an organic electrolyte sandwiched between a pair of carbon-based electrodes. The energy storage is achieved by separating and storing electrical charge in the electrochemical double layers that are created at the interfaces between the electrodes and the electrolyte. Important characteristics of these devices are the energy density and power density that they can provide, which are both largely determined by the properties of the carbon that is incorporated into the electrodes.